Disp fx of proximal phalanx of r thm, subs for fx w malunion

This code describes a situation where a patient has a malunion of a previously treated fracture of the proximal phalanx of their right thumb. A malunion indicates that the bone has healed, but in an unsatisfactory or deformed position, which may lead to functional impairment. This specific code is used during follow-up care for this complication.

This code is appropriate for encounters where a patient is being evaluated or treated for a right thumb proximal phalanx fracture that has healed incorrectly. This includes visits for assessment of the malunion, planning for corrective surgery, or post-operative care following a procedure to address the malunion. It should be used after the initial treatment of the fracture has concluded and the malunion has been identified.

• Ensure documentation clearly states "malunion" and specifies the right thumb's proximal phalanx.
• Verify that the encounter is for follow-up care related to the malunion, not the initial fracture treatment.
• Always sequence this code after any relevant external cause codes if applicable.